Hyperhidrosis is a medical condition in which a person sweats excessively and unpredictably. People with hyperhidrosis can sweat even when the temperature is cool, and when they are at rest. Excessive sweating (hyperhidrosis) in the palms, soles, and armpits (axillae) is not only embarrassing, but can also be a sign of an underlying disease. Before dismissing excessive sweating as simply being due to emotions or social situations, it is important to rule out other possible causes.

Hyperhidrosis can be caused by dysfunction of the autonomic nervous system (ANS). Sweating is controlled through the opposing actions of the sympathetic and parasympathetic divisions of the ANS. If the sympathetic system (“fight or flight” system) is overly stimulated, for instance, excessive sweating will occur. This cause of hyperhidrosis can now be easily treated with a simple outpatient surgical procedure.

The most common diseases to cause excessive sweating are diabetes and hyperthyroidism. Diabetes mellitus is a disease of poor glucose (sugar) control. Over time, diabetes disrupts the proper function of the ANS. Diabetes is also associated with obesity, which itself can cause excessive sweating. An easy way to find out if you have diabetes is to have your blood glucose (sugar) checked by your primary doctor with a simple blood test.

The thyroid gland, which is located in the neck, produces important hormones in response to signals in the brain. These hormones act by either increasing or decreasing the body’s metabolic rate. Hyperthyroidism occurs when the thyroid is overactive and secretes more hormone than in the usual resting state. This stimulates a faster metabolic rate in the body, producing increased sweating, nervousness, heart palpitations and weight loss. If you are experiencing any of these symptoms, a doctor can check your thyroid function and level of thyroid hormones through a simple blood test.

Other causes of excessive sweating include infections, menopause, certain medications, alcoholism, and certain types of cancers. Infections often are associated with a fever, as the body tries to fight off the bacteria or virus causing the infection. If you are experiencing other symptoms associated with sweating, such as a cough, nausea, vomiting, or fatigue, it is important to take your temperature using a thermometer, and also make an appointment to see your primary doctor. Normal body temperature is 98.6 degrees Fahrenheit taken orally.

Menopause is the termination of monthly menstrual cycles in females, usually around the age 50. Common symptoms include sudden hot flashes and night sweats. If you have noticed an irregularity in your menstrual cycle, and are having hot flashes or night sweats, you should see your primary doctor or gynecologist to discuss various treatment options.

A more serious cause of excessive sweating, especially night sweats, is cancer. For example, Hodgkin’s disease is a type of lymphoma often associated with night sweats. Patients also usually present with enlarged lymph nodes in the neck, axilla, or groin, unexplained fever, pruritis (itching), and weight loss. This requires a more complete work-up by your doctor including blood tests, x-rays, and CT scans. All other possible causes of excessive sweating need to be excluded first.

But note, localized sweating in the palms, armpits or feet in an otherwise healthy person is primary hyperhidrosis. These can simply be treated with great success with endoscopic thoracic sympathectomy (ETS).